The present invention relates to an electronic instrument casing for use in a portable radio instrument, a transportable radio instrument and the like.
FIG. 5 of the attached drawings shows an example of a conventional electronic instrument casing of the kind referred to above. In FIG. 5, the reference numeral 1 denotes a wireless or radio unit which is provided with a speaker 4 on an upper portion of a chassis 2 and an operation panel 3 on a side of the chassis 2. The reference numeral 5 denotes a rectangular tubular case for detachably receiving the radio unit 1, which has a battery-unit or cell-unit mounting portion 6 at a bottom thereof. The reference numeral 7 denotes a cell unit which is detachably mounted on the cell-unit mounting portion 6 of the tubular case 5. The cell unit 7 has at an upper portion thereof a pair of guide rails 8 which are adapted to be fitted in the cell-unit mounting portion 6. Alternatively, the speaker 4 may be provided on the tubular case 5. After the radio unit 1 has been received in the tubular case 5, the guide rails 8 of the cell unit 7 are fitted in the cell-unit mounting portion 6 at the bottom of the tubular case 5, whereby power is supplied from the cell unit 7 to the radio unit 1. Accordingly, inputting operation is performed on the operation panel 3, whereby radio or wireless talking or speaking can be done through the speaker 4 and a microphone (not shown).
In the conventional electronic instrument casing, however, when an option unit such as a recording and reproducing (playback) unit or the like is to be added thereto, such operation is required, in which the radio unit 1 is once extracted from the tubular case 5, the option unit is fixedly mounted on the chassis 2 and, subsequently, the radio unit 1 is again received in the tubular case 5. For this reason, when the radio unit 1 is mounted on and demounted from the tubular case 5, an electric contacting condition sometimes changes to make electric performance unstable. Further, there is a problem that, when the option unit is to be mounted on the radio unit 1, metal waste and refuse enter into the radio unit 1, so that mounting parts are damaged or broken down.